Tsarnaev, 19, turned and looked repeatedly into the full-house crowd that assembled in federal court here as he entered not guiilty pleas to 30 counts stemming from the Boston Marathon bombing. He spoke in a Russian accent.

Tsarnaev was wearing a partially unbuttoned orange jumpsuit and a black t-shirt. He looked over his right shoulder as if to see who was there. Judge Marianne Bowler said that present were 30 victims of the bombing and family members.

He wore a cast on his left arm and hand and displayed a crooked smile to two sisters, both in Muslim garb, seated in the courtroom.

The arraignment was his first public appearance since he was arrested April 19.

Public defender Judy Clarke tried to enter a single "not guilty" plea on Tsarnaev's behalf and have it apply to all counts in the indictment. But Bowler asked that Tsarnaev speak for himself and that all the charges be read aloud.

Flanked by his two attorneys, Tsarnaev said only two words ‚?? "not guilty" ‚?? repeating them seven times as prosecutors read the charges against him. Each of the 30 counts could bring a life-in-prison sentence. Seventeen are also eligible for the death penalty if the government decides to seek capital punishment.

Tsarnaev looked unable to sit still in the courtroom. His hair was long and unkempt. His eyes appeared irritated; the skin around them was dark. His jaw functioned awkwardly. When he looked over his shoulder at portions of the crowd, he repeatedly shifted his jaw and mouth to the right side of his face.

His voice, however, was strong. Soon after his arrest, concerns had surfaced that his throat might have undergone permanent injury in confrontations with police. He spoke with an accent reflective of his ethnic Chechen heritage. He spoke clearly and loudly.

Hours before the hearing, Tsarnaev arrived at the federal courthouse in a four-vehicle motorcade.

Several of the charges could bring the death penalty for Tsarnaev, 19, accused in the April 15 blasts that killed three people and wounded more than 200. Tsarnaev also is accused of killing an MIT police officer.

His brother, Tamerlan Tsarnaev, was killed in a shootout with police following a massive manhunt three days after the bombings. Dzhokhar Tsarnaev was captured the next day -- wounded and bloodied from the shootout -- after a Watertown homeowner noticed blood on his dry-docked boat. Police found the suspect hiding inside.

Authorities say the brothers were inspired by al-Qaeda publications and that Dzhokhar Tsarnaev left a confession in the boat justifying the bombings as payback for U.S. military action in Muslim countries.

He wrote that the U.S. government was "killing our innocent civilians."

"I don't like killing innocent people," he said, but also wrote: "I can't stand to see such evil go unpunished. ‚?¶ We Muslims are one body, you hurt one you hurt us all."

Tsarnaev's arrest stunned those who knew him as a likable high school athlete in Cambridge, Mass., where he lived with his older brother after his parents left for Russia.

The indictment also said that, sometime before the bombings, Tsarnaev downloaded Internet material from Islamic extremists that advocated violence against the perceived enemies of Islam.

Three people - Martin Richard, 8, Krystle Marie Campbell, 29, and Lingzi Lu, 23 - were killed by the bombs, which were improvised from pressure cookers. Authorities say the Tsarnaevs also killed Massachusetts Institute of Technology officer Sean Collier days later while they were on the run.